RETIREMENT PLANS (Tables)

6 Months Ended

Mar. 31, 2021

Retirement Benefits [Abstract]

Schedule of components of net periodic benefit cost (income)

The following tables detail the components of net periodic benefit (income) cost for Barnwell’s retirement plans:

	Pension Plan				SERP				Postretirement Medical
	Three months ended March 31,
	2021		2020		2021		2020		2021		2020
Interest cost	$	64,000	$	72,000	$	13,000	$	15,000	$	18,000	$	20,000
Expected return on plan assets	(137,000)		(172,000)		—		—		—		—
Amortization of net actuarial loss	10,000		—		—		—		23,000		20,000
Net periodic benefit (income) cost	$	(63,000)	$	(100,000)	$	13,000	$	15,000	$	41,000	$	40,000

	Pension Plan				SERP				Postretirement Medical
	Six months ended March 31,
	2021		2020		2021		2020		2021		2020
Service cost	$	—	$	50,000	$	—	$	3,000	$	—	$	—
Interest cost	129,000		155,000		26,000		33,000		36,000		40,000
Expected return on plan assets	(274,000)		(335,000)		—		—		—		—
Amortization of prior service cost (credit)	—		1,000		—		(1,000)		—		—
Amortization of net actuarial loss	20,000		35,000		—		5,000		46,000		40,000
Curtailment cost (income)	—		53,000		—		(53,000)		—		—
Net periodic benefit (income) cost	$	(125,000)	$	(41,000)	$	26,000	$	(13,000)	$	82,000	$	80,000